Crosslinkable rubber composition
CA 2004541 C · Owner: Colvin, Howard Allen · Inventors: Weinstein, Arthur Howard; Colvin, Howard Allen; Parker, Dane Kenton
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
It is sometimes desirable to cure rubber compositions utilizing non-sulfur curing agents. The subject invention reveals rubber compositions which can be cured without utilizing sulfur or sulfur containing compounds. The subject invention more specifically discloses a rubber composition which can be crosslinked by heating which is comprised of (1) at least one rubber having pendant blocked isocyanate groups bound thereto; and (2) at least one compound which contains at least 2 Zerewitinoff active hydrogens. This invention also discloses crosslinking of elastomer compounds containing (1) at least one rubber having functionalized groups containing at least one Zerewitinoff active hydrogen and …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed December 4, 1989 and granted July 7, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 4, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 4, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.